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[Reading Comprehension]

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文章：

Line         Milankovitch proposed in the early twentieth
  century that the ice ages were caused by variations
  in the Earth’s orbit around the Sun. For some time
  this theory was considered untestable, largely
(5) because there was no sufficiently precise
  chronology of the ice ages with which the orbital
  variations could be matched.
       To establish such a chronology it is necessary to
  determine the relative amounts of land ice that
(10) existed at various times in the Earth’s past. A
  recent discovery makes such a determination
  possible: relative land-ice volume for a given period
  can be deduced from the ratio of two oxygen
  isotopes, 16 and 18, found in ocean sediments.
(15) Almost all the oxygen in water is oxygen 16, but a
  few molecules out of every thousand incorporate the
  heavier isotope 18. When an ice age begins, the
  continental ice sheets grow, steadily reducing the
  amount of water evaporated from the ocean that
(20) will eventually return to it. Because heavier
  isotopes tend to be left behind when water
  evaporates from the ocean surfaces, the remaining
  ocean water becomes progressively enriched in
  oxygen 18. The degree of enrichment can be
(25) determined by analyzing ocean sediments of the
  period, because these sediments are composed of
  calcium carbonate shells of marine organisms,
  shells that were constructed with oxygen atoms
  drawn from the surrounding ocean. The higher the
(30) ratio of oxygen 18 to oxygen 16 in a sedimentary
  specimen, the more land ice there was when the
  sediment was laid down.
       As an indicator of shifts in the Earth’s climate,
  the isotope record has two advantages. First, it is a
(35) global record: there is remarkably little variation in
  isotope ratios in sedimentary specimens taken from
  different continental locations. Second, it is a
  more continuous record than that taken from rocks
  on land. Because of these advantages, sedimentary
(40) evidence can be dated with sufficient accuracy
  by radiometric methods to establish a precise
  chronology of the ice ages. The dated isotope
  record shows that the fluctuations in global ice
  volume over the past several hundred thousand
(45) years have a pattern: an ice age occurs roughly once
  every 100,000 years. These data have established
  a strong connection between variations in the Earth’s
  orbit and the periodicity of the ice ages.
       However, it is important to note that other
(50) factors, such as volcanic particulates or variations
  in the amount of sunlight received by the Earth,
  could potentially have affected the climate. The
  advantage of the Milankovitch theory is that it
  is testable; changes in the Earth’s orbit can be
(55) calculated and dated by applying Newton’s laws of
  gravity to progressively earlier configurations of the
  bodies in the solar system. Yet the lack of
  information about other possible factors affecting
  global climate does not make them unimportant.


题目：

It can be inferred from the passage that calcium carbonate shells

选项:

A、are not as susceptible to deterioration as rocks
B、are less common in sediments formed during an ice age
C、are found only in areas that were once covered by land ice
D、contain radioactive material that can be used to determine a sediment’s isotopic composition
E、reflect the isotopic composition of the water at the time the shells were formed

答案:

E
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[Reading Comprehension]

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文章：

Jon Clark’s study of the effect of the modernization of a telephone exchange on exchange maintenance work and workers is a solid contribution to a debate that encompasses two lively issues in the history and sociology of technology: technological determinism and social constructivism.

Clark makes the point that the characteristics of a technology have a decisive influence on job skills and work organization. Put more strongly, technology can be a primary determinant of social and managerial organization. Clark believes this possibility has been obscured by the recent sociological fashion, exemplified by Braverman’s analysis, that emphasizes the way machinery reflects social choices. For Braverman, the shape of a technological system is subordinate to the manager’s desire to wrest control of the labor process from the workers. Technological change is construed as the outcome of negotiations among interested parties who seek to incorporate their own interests into the design and con

题目：

Which of the following statements about Clark’s study of the telephone exchange can be inferred from information in the passage?

选项:

A、Clark's reason for undertaking the study was to undermine Braverman's analysis of the function of technology.Clark's study suggests that the implementation of technology should be discussed in the context of conflict between labor and management.
B、Clark examined the impact of changes in the technology of switching at the exchange in terms of overall operations and organization.
C、Clark concluded that the implementation of new switching technology was equally beneficial to management and labor.
D、Clark's analysis of the change in switching systems applies only narrowly to the situation at the particular exchange that he studied.

答案:

C
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[Sentence Correction]

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题目：

The Baldrick Manufacturing Company has for several years followed a policy aimed at decreasing operating costs and improving the efficiency of its distribution system.

选项:

A、aimed at decreasing operating costs and improvingaimed at the decreasing of operating costs and to improve
B、aiming at the decreasing of operating costs and improving
C、the aim of which is the decreasing of operating costs and improving
D、with the aim to decrease operating costs and to improve

答案:

A
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[Critical Reasoning]

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题目：

An overly centralized economy, not the changes in the climate, is responsible for the poor agricultural production in Country X since its new government came to power. Neighboring Country Y has experienced the same climatic conditions, but while agricultural production has been falling in Country X, it has been rising in Country Y.

Which of the following, if true, would most weaken the argument above?

选项:

A、Industrial production also is declining in Country X.
B、Whereas Country Y is landlocked, Country X has a major seaport.
C、Both Country X and Country Y have been experiencing drought conditions.
D、The crops that have always been grown in Country X are different from those that have always been grown in Country Y.
E、Country X's new government instituted a centralized economy with the intention of ensuring an equitable distribution of goods.

答案:

D
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文章：

Line        When asteroids collide, some collisions cause
 an asteroid to spin faster; others slow it down. If
 asteroids are all monoliths—single rocks—undergoing
 random collisions, a graph of their rotation rates
(5)should show a bell-shaped distribution with statistical
 “tails” of very fast and very slow rotators. If asteroids
 are rubble piles, however, the tail representing the
 very fast rotators would be missing, because any
 loose aggregate spinning faster than once every few
(10)hours (depending on the asteroid’s bulk density)
 would fly apart. Researchers have discovered that
 all but five observed asteroids obey a strict limit on
 rate of rotation. The exceptions are all smaller than
 200 meters in diameter, with an abrupt cutoff for
(15)asteroids larger than that.
      The evident conclusion—that asteroids larger than
 200 meters across are multicomponent structures
 or rubble piles—agrees with recent computer modeling
 of collisions, which also finds a transition at that
(20)diameter. A collision can blast a large asteroid to bits,
 but after the collision those bits will usually move
 slower than their mutual escape velocity. Over several
 hours, gravity will reassemble all but the fastest
 pieces into a rubble pile. Because collisions among
(25)asteroids are relatively frequent, most large bodies
 have already suffered this fate. Conversely, most
 small asteroids should be monolithic, because impact
 fragments easily escape their feeble gravity.


题目：

According to the passage, which of the following is a prediction that is based on the strength of the gravitational attraction of small asteroids?

选项:

答案:

B
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[Reading Comprehension]

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文章：

A meteor stream is composed of dust particles that have been ejected from a parent comet at a variety of velocities. These particles follow the same orbit as the parent comet, but due to their differing velocities they slowly gain on or fall behind the disintegrating comet until a shroud of dust surrounds the entire cometary orbit. Astronomers have hypothesized that a meteor stream should broaden with time as the dust particles' individual orbits are perturbed by planetary gravitational fields. A recent computer-modeling experiment tested this hypothesis by tracking the influence of planetary gravitation over a projected 5,000-year period on the positions of a group of hypothetical dust particles. In the model, the particles were randomly distributed throughout a computer simulation of the orbit of an actual meteor stream, the Gemini. The researcher found, as expected, that the computer-model stream broadened with time. Conventional theories, however, predicted that the distribution of particles would be increasingly dense toward the center of a meteor stream. Surprisingly, the computer-model meteor stream gradually came to resemble a thick-walled, hollow pipe.
Whenever the Earth passes through a meteor stream, a meteor shower occurs. Moving at a little over 1,500,000 miles per day around its orbit, the Earth would take, on average, just over a day to cross the hollow, computer-model Geminid stream if the stream were 5,000 years old. Two brief periods of peak meteor activity during the shower would be observed, one as the Earth entered the thick-walled "pipe" and one as it exited. There is no reason why the Earth should always pass through the stream's exact center, so the time interval between the two bursts of activity would vary from one year to the next.
Has the predicted twin-peaked activity been observed for the actual yearly Geminid meteor shower? The Geminid data between 1970 and 1979 show just such a bifurcation, a secondary burst of meteor activity being dearly visible at an average of 19 hours (1,200,000 miles) after the first burst. The time intervals between the bursts suggest the actual Geminid stream is about 3,000 years old.

题目：

the passage suggests that which of the following is a prediction concerning meteor streams that can be derived from both the conventional theories mentioned in the highlighted text and the new computer derived theory?

选项:

A、Dust particles in a meteor stream will usually be distributed evenly throughout any cross section of the stream.
B、The orbits of most meteor streams should cross the orbit of the Earth at some point and give rise to a meteor shower. 
C、Over time the distribution of dust in a meteor stream will usually become denser at the outside edges of the stream than at the center. 
D、Meteor showers caused by older meteor streams should be, on average, longer in duration than those caused by very young meteor streams. 
E、The individual dust particles in older meteor streams should be, on average, smaller than those that compose younger meteor streams.

答案:

D
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[Problem Solving]

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题目：

Bouquets are to be made using white tulips and red tulips, and the ratio of the number of white tulips to the number of red tulips is to be the same in each bouquet. If there are 15 white tulips and 85 red tulips available for the bouquets, what is the greatest number of bouquets that can be made using all the tulips available?

选项:

A、The first is the position the argument advocates; the second presents grounds for rejecting an alternative position.
B、The first is the position the argument advocates; the second is an alternative position that the argument rejects.
C、 The first presents a strategy for achieving a certain goal; the second presents a drawback to that strategy.
D、The first presents a strategy for achieving a certain goal; the second presents grounds for preferring a different goal.
E、The first presents a strategy that, according to the argument, is ineffective; the second presents a way of improving the effectiveness of that strategy.

答案:

B
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[Sentence Correction]

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题目：

The Glass House Mountains in Queensland, Australia, were sighted in 1770 by the English navigator Captain James Cook, by whom they were named supposedly because its sheer wet rocks glistened like glass.

选项:

A、by whom they were named supposedly because its
B、by whom they were named supposedly and their
C、naming them supposedly since their
D、who so named them supposedly because their
E、who so named it since supposedly their

答案:

D
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[Critical Reasoning]

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题目：

Hunter: Many people blame hunters alone for the decline in Greenrock National Forest’s deer population over the past ten years. Yet clearly, black bears have also played an important role in this decline. In the past ten years, the forest’s protected black bear population has risen sharply, and examination of black bears found dead in the forest during the deer hunting season showed that a number of them had recently fed on deer.

In the hunter’s argument, the portion in boldface plays which of the following roles?

选项:

A、It is the main conclusion of the argument.
B、It is a finding that the argument seeks to explain.
C、It is an explanation that the argument concludes is correct.
D、It provides evidence in support of the main conclusion of the argument.
E、It introduces a judgment that the argument opposes.

答案:

E
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[Critical Reasoning]

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题目：

Which of the following, if true, most logically completes the argument?

Some dairy farmers in the province of Takandia want to give their cows a synthetic hormone that increases milk production. Many Takandians, however, do not want to buy milk from cows given the synthetic hormone. For this reason Takandia's legislature is considering a measure requiring milk from cows given the hormone to be labeled as such. Even if the measure is defeated, dairy farmers who use the hormone will probably lose customers, since __________.

选项:

答案:

C
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[Undefined]

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Art historian: Unlike many artistic traditions that sought to depict plants native to the local area in a seasonally appropriate way (for example, depicting scenes of spring with the plants in the appropriate stages of development for that season), seventeenth-century Dutch artists specializing in flower paintings almost exclusively chose to depict exotic species of flowers from outside the local area. Painting such species was worthwhile primarily because the art-buying public had developed a strong preference for images of the exotic. The great botanical centers of the time gave the artists direct access to such flowers, which the artists would freely combine in a single painting, regardless of whether the combined species occurred together in the wild, and depicted each in full bloom, regardless of whether those species bloomed at the same time in nature.

Statement: The art historian makes the point that the species of flowers these Dutch artists chose to paint were 1 largely because the species were 2 .

Select for 1 and for 2 the options that complete the statement so that it is most strongly supported by the information provided. Make only two selections, one in each column.
我选的CE，和EC有什么区别？怎么选出EC的？
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[Undefined]

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An unusually severe winter occurred in Europe after the continent was blanketed by a blue haze resulting from the eruption of the Laki Volcano in the European republic of Iceland in the summer of 1984.  Thus, it is evident that major eruptions cause the atmosphere to become cooler than it would be otherwise.
Which of the following statements, if true, most seriously weakens the argument above?
C选项为什么就不会有张冠李戴的问题呢，1984和1982的气候情况能一样吗，C里的火山就可以试用于原文的火山吗
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[Undefined]

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The rate of a certain chemical reaction is directly proportional to the square of the concentration of chemical A present and inversely proportional to the concentration of chemical B present. If the concentration of chemical B is increased by 100 percent, which of the following is closest to the percent change in the concentration of chemical A required to keep the reaction rate unchanged?
为什么这个题一定是相乘不能是相加呢？y=k1A方-k2B （k1,k2大于0 ），也满足题目说的与A方成正比与B成反比啊？但是这道题只有相乘的情况才能选出正确答案
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[Undefined]

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Tiger beetles are such fast runners that they can capture virtually any nonflying insect.  However, when running toward an insect, the beetles intermittently stop, and then, a moment later, resume their attack.  Perhaps they cannot maintain their pace and must pause for a moment's rest; but an alternative hypothesis is that while running tiger beetles are unable to process the resulting rapidly changing visual information, and so quickly go blind and stop.
 
Which of the following, if discovered in experiments using artificially moved prey insects, would support one of the two hypotheses and undermine the other?
答案C是怎么支持一个猜想又削弱另一个猜想的？
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2745浏览

[GWD]

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The author of the passage implies that which of the following is a possible partial explanation for acquisition behavior during the 1970's and 1980's?
请解释这道题为什么不选C或E，除了正确选项B，我认为文中也正确地提到了这两个选项可以解释acquisition behavior during 1970s and 80s
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[OG]

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The primary purpose of the passage is to
为什么选E不选B
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[Undefined]

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Club X has more than 10 but fewer than 40 members. Sometimes the members sit at tables with 3 members at one table and 4 members at each of the other tables, and sometimes they sit at tables with 3 members at one table and 5 members at each of the other tables. If they sit at tables with 6 members at each table except one and fewer than 6 members at that one table, how many members will be at the table that has fewer than 6 members?
提问小梅老师 这道题求讲一下 我没什么思路 带入数字得的是3
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[Undefined]

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A photography dealer ordered 60 Model X cameras to be sold for $250 each, which represents a 20 percent markup over the dealer's initial cost for each camera. Of the cameras ordered, 6 were never sold and were returned to the manufacturer for a refund of 50 percent of the dealer's initial cost. What was the dealer's approximate profit or loss as a percent of the dealer's initial cost for the 60 cameras?
请问小梅老师 这道题讲讲一下 我算的是19% 原来成本是200每个 亏了6个 每个亏100. 最后得不出答案
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[Undefined]

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Analytical!
请问may老师，这题该用什么思路来做？
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[Undefined]

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Analytical!
请问张老师，这道题为什么D不对？我有我觉得second paragraph最后一句话特别指向D
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